As mobile wireless devices and applications become increasingly prevalent, location and positioning services based on global positioning system (GPS) systems continue to flourish. Current GPS receiver technology allows for low cost, high performance GPS receivers to be installed in an increasing number of mobile devices.
In the United States the FCC 911 mandate addresses the requirement for location of cell phones during emergency situations available to dispatchers. Known as Assisted GPS, generally abbreviated as A-GPS, is a system which can, under certain conditions, improve the startup performance, or Time To First Fix (TTFF) of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones to address the 911 mandate.